I'm also very happy that the NTSB gave ATC 50% of the responsibility for
Scott's accident.

Just to clarify, the NTSB did not apportion the responsibility, but just
listed probable cause as:

"The pilot's failure to obtain updated en route weather information, which
resulted in his continued instrument flight into a widespread area of severe
convective activity, and the air traffic controller's failure to provide
adverse weather avoidance assistance, as required by Federal Aviation
Administration directives, both of which led to the airplane's encounter with
a severe thunderstorm and subsequent loss of control."

I don't know if there's a civil trial associated with the accident, but if
there is, that's where the judge or jury might set percentages.